1. Field of the Invention
The invention relates to a corrugated cardboard machine and a method of producing an endless web of corrugated cardboard.
2. Background Art
During the production of endless webs of corrugated cardboard, a corrugated web is at first coated with glue by means of a first gluing device and joined to a first liner to form a single-face web of corrugated cardboard. Afterwards, the corrugated web is coated with glue on the side opposite the first liner by means of a second gluing device and joined to a second liner to form a double-face web of corrugated cardboard. As at least some of the orders to be processed have an order width which substantially equals the width of the webs, the webs are coated with glue and bonded together up to their edges. A disadvantage is that when the webs are coated with glue and bonded together up to their edges, glue may escape from the sides and contaminate components of the corrugated cardboard machine such as the grooving rollers or the heating plates. Such contaminations result in a higher wear of the components so that in order to prevent said wear, the components require more frequent cleaning. The corrugated cardboard machine is switched off during cleaning which is undesirable for reasons of economy. Furthermore, the corrugated cardboard machine produces rejects when a particular level of contamination is reached.
A gluing device is disclosed in U.S. Pat. No. 5,101,761 which comprises lateral plates so as to prevent glue applied by means of a glue application roller from escaping from the sides. The gluing device further comprises glue dams which are displaceable crosswise to a direction of conveyance of the corrugated web to be coated with glue, thus enabling an application width of the gluing device to be adapted to the web width of the corrugated web. Since the webs are coated with glue and bonded together up to their edges, this gluing device also has the disadvantages described above.